#region Apache License
//
// Licensed to the Apache Software Foundation (ASF) under one or more 
// contributor license agreements. See the NOTICE file distributed with
// this work for additional information regarding copyright ownership. 
// The ASF licenses this file to you under the Apache License, Version 2.0
// (the "License"); you may not use this file except in compliance with 
// the License. You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
#endregion

// .NET Compact Framework 1.0 has no support for reading assembly attributes
#if !NETCF

using System;
using System.Reflection;

using log4net.Util;
using log4net.Repository;
using log4net.Core;

namespace log4net.Config
{
  /// <summary>
  /// Assembly level attribute to configure the <see cref="SecurityContextProvider"/>.
  /// </summary>
  /// <remarks>
  /// <para>
  /// This attribute may only be used at the assembly scope and can only
  /// be used once per assembly.
  /// </para>
  /// <para>
  /// Use this attribute to configure the <see cref="XmlConfigurator"/>
  /// without calling one of the <see cref="M:XmlConfigurator.Configure()"/>
  /// methods.
  /// </para>
  /// </remarks>
  /// <author>Nicko Cadell</author>
  [AttributeUsage(AttributeTargets.Assembly)]
  [Serializable]
  public sealed class SecurityContextProviderAttribute : ConfiguratorAttribute
  {
    #region Constructor

    /// <summary>
    /// Construct provider attribute with type specified
    /// </summary>
    /// <param name="providerType">the type of the provider to use</param>
    /// <remarks>
    /// <para>
    /// The provider specified must subclass the <see cref="SecurityContextProvider"/>
    /// class.
    /// </para>
    /// </remarks>
    public SecurityContextProviderAttribute(Type providerType) : base(100) /* configurator priority 100 to execute before the XmlConfigurator */
    {
      m_providerType = providerType;
    }

    #endregion

    #region Public Instance Properties

    /// <summary>
    /// Gets or sets the type of the provider to use.
    /// </summary>
    /// <value>
    /// the type of the provider to use.
    /// </value>
    /// <remarks>
    /// <para>
    /// The provider specified must subclass the <see cref="SecurityContextProvider"/>
    /// class.
    /// </para>
    /// </remarks>
    public Type ProviderType
    {
      get { return m_providerType; }
      set { m_providerType = value; }
    }

    #endregion Public Instance Properties

    #region Override ConfiguratorAttribute

    /// <summary>
    /// Configures the SecurityContextProvider
    /// </summary>
    /// <param name="sourceAssembly">The assembly that this attribute was defined on.</param>
    /// <param name="targetRepository">The repository to configure.</param>
    /// <remarks>
    /// <para>
    /// Creates a provider instance from the <see cref="ProviderType"/> specified.
    /// Sets this as the default security context provider <see cref="SecurityContextProvider.DefaultProvider"/>.
    /// </para>
    /// </remarks>
    public override void Configure(Assembly sourceAssembly, ILoggerRepository targetRepository)
    {
      if (m_providerType == null)
      {
        LogLog.Error(declaringType, "Attribute specified on assembly [" + sourceAssembly.FullName + "] with null ProviderType.");
      }
      else
      {
        LogLog.Debug(declaringType, "Creating provider of type [" + m_providerType.FullName + "]");

        SecurityContextProvider provider = Activator.CreateInstance(m_providerType) as SecurityContextProvider;

        if (provider == null)
        {
          LogLog.Error(declaringType, "Failed to create SecurityContextProvider instance of type [" + m_providerType.Name + "].");
        }
        else
        {
          SecurityContextProvider.DefaultProvider = provider;
        }
      }
    }

    #endregion

    #region Private Instance Fields

    private Type m_providerType = null;

    #endregion Private Instance Fields

    #region Private Static Fields

    /// <summary>
    /// The fully qualified type of the SecurityContextProviderAttribute class.
    /// </summary>
    /// <remarks>
    /// Used by the internal logger to record the Type of the
    /// log message.
    /// </remarks>
    private static readonly Type declaringType = typeof(SecurityContextProviderAttribute);

    #endregion Private Static Fields
  }
}

#endif // !NETCF